feat(comments): paginate life post and entity discussion comments

Implement cursor-based pagination for Life and Entity comments
Optimize Life Post queries to return comment counts and previews
Add "Load more" functionality to frontend discussion panels

system-wordings.ts

@@ -483,6 +483,8 @@ export const systemWordingMessages = {
         postingReply: 'Posting reply',
         cancelReply: 'Cancel reply',
         noComments: 'No comments yet',
+        loadingComments: 'Loading comments',
+        loadMoreComments: 'Load more comments',
         deleteComment: 'Delete comment',
         deleteCommentConfirm: 'Delete this comment?',
         commentDeleted: 'Comment deleted',
@@ -659,6 +661,7 @@ export const systemWordingMessages = {
       replyFailed: 'Reply failed',
       deleteFailed: 'Delete failed',
       loading: 'Loading discussion',
+      loadMore: 'Load more comments',
       empty: 'No discussion yet',
       emptyHint: 'Start a new discussion now.',
       loginPrompt: 'Log in with a verified email to comment.',
@@ -1265,6 +1268,8 @@ export const systemWordingMessages = {
         postingReply: '回复中',
         cancelReply: '取消回复',
         noComments: '暂无评论',
+        loadingComments: '正在加载评论',
+        loadMoreComments: '加载更多评论',
         deleteComment: '删除评论',
         deleteCommentConfirm: '确认删除这条评论？',
         commentDeleted: '评论已删除',
@@ -1441,6 +1446,7 @@ export const systemWordingMessages = {
       replyFailed: '回复失败',
       deleteFailed: '删除失败',
       loading: '正在加载讨论',
+      loadMore: '加载更多评论',
       empty: '暂无讨论',
       emptyHint: '现在发起新的讨论。',
       loginPrompt: '使用已验证邮箱登录后即可评论。',